Commit 16dad780 authored by Tejun Heo's avatar Tejun Heo
Browse files

cgroup: Rename cgroup lifecycle hooks to cgroup_task_*() 



The current names cgroup_exit(), cgroup_release(), and cgroup_free() are
confusing because they look like they're operating on cgroups themselves when
they're actually task lifecycle hooks. For example, cgroup_init() initializes
the cgroup subsystem while cgroup_exit() is a task exit notification to
cgroup. Rename them to cgroup_task_exit(), cgroup_task_release(), and
cgroup_task_free() to make it clear that these operate on tasks.

Cc: Dan Schatzberg <dschatzberg@meta.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: default avatarChen Ridong <chenridong@huawei.com>
Signed-off-by: default avatarTejun Heo <tj@kernel.org>
parent d5cf4d34

include/linux/cgroup.h

+6 −6
Original line number Diff line number Diff line
@@ -137,9 +137,9 @@ extern void cgroup_cancel_fork(struct task_struct *p, 
			       struct kernel_clone_args *kargs);

extern void cgroup_post_fork(struct task_struct *p,

			     struct kernel_clone_args *kargs);

void cgroup_exit(struct task_struct *p);

void cgroup_release(struct task_struct *p);

void cgroup_free(struct task_struct *p);

void cgroup_task_exit(struct task_struct *p);

void cgroup_task_release(struct task_struct *p);

void cgroup_task_free(struct task_struct *p);



int cgroup_init_early(void);

int cgroup_init(void);
@@ -680,9 +680,9 @@ static inline void cgroup_cancel_fork(struct task_struct *p, 
				      struct kernel_clone_args *kargs) {}

static inline void cgroup_post_fork(struct task_struct *p,

				    struct kernel_clone_args *kargs) {}

static inline void cgroup_exit(struct task_struct *p) {}

static inline void cgroup_release(struct task_struct *p) {}

static inline void cgroup_free(struct task_struct *p) {}

static inline void cgroup_task_exit(struct task_struct *p) {}

static inline void cgroup_task_release(struct task_struct *p) {}

static inline void cgroup_task_free(struct task_struct *p) {}



static inline int cgroup_init_early(void) { return 0; }

static inline int cgroup_init(void) { return 0; }

kernel/cgroup/cgroup.c

+6 −5
Original line number Diff line number Diff line
@@ -944,7 +944,8 @@ static void css_set_move_task(struct task_struct *task, 
		/*

		 * We are synchronized through cgroup_threadgroup_rwsem

		 * against PF_EXITING setting such that we can't race

		 * against cgroup_exit()/cgroup_free() dropping the css_set.

		 * against cgroup_task_exit()/cgroup_task_free() dropping

		 * the css_set.

		 */

		WARN_ON_ONCE(task->flags & PF_EXITING);
@@ -6972,13 +6973,13 @@ void cgroup_post_fork(struct task_struct *child, 
}



/**

 * cgroup_exit - detach cgroup from exiting task

 * cgroup_task_exit - detach cgroup from exiting task

 * @tsk: pointer to task_struct of exiting process

 *

 * Description: Detach cgroup from @tsk.

 *

 */

void cgroup_exit(struct task_struct *tsk)

void cgroup_task_exit(struct task_struct *tsk)

{

	struct cgroup_subsys *ss;

	struct css_set *cset;
@@ -7010,7 +7011,7 @@ void cgroup_exit(struct task_struct *tsk) 
	} while_each_subsys_mask();

}



void cgroup_release(struct task_struct *task)

void cgroup_task_release(struct task_struct *task)

{

	struct cgroup_subsys *ss;

	int ssid;
@@ -7027,7 +7028,7 @@ void cgroup_release(struct task_struct *task) 
	}

}



void cgroup_free(struct task_struct *task)

void cgroup_task_free(struct task_struct *task)

{

	struct css_set *cset = task_css_set(task);

	put_css_set(cset);

kernel/exit.c

+2 −2
Original line number Diff line number Diff line
@@ -257,7 +257,7 @@ void release_task(struct task_struct *p) 
	rcu_read_unlock();



	pidfs_exit(p);

	cgroup_release(p);

	cgroup_task_release(p);



	/* Retrieve @thread_pid before __unhash_process() may set it to NULL. */

	thread_pid = task_pid(p);
@@ -967,7 +967,7 @@ void __noreturn do_exit(long code) 
	exit_thread(tsk);



	sched_autogroup_exit_task(tsk);

	cgroup_exit(tsk);

	cgroup_task_exit(tsk);



	/*

	 * FIXME: do that only when needed, using sched_exit tracepoint

kernel/fork.c

+1 −1
Original line number Diff line number Diff line
@@ -738,7 +738,7 @@ void __put_task_struct(struct task_struct *tsk) 
	unwind_task_free(tsk);

	sched_ext_free(tsk);

	io_uring_free(tsk);

	cgroup_free(tsk);

	cgroup_task_free(tsk);

	task_numa_free(tsk, true);

	security_task_free(tsk);

	exit_creds(tsk);

kernel/sched/autogroup.c

+2 −2
Original line number Diff line number Diff line
@@ -178,8 +178,8 @@ autogroup_move_group(struct task_struct *p, struct autogroup *ag) 
	 * this process can already run with task_group() == prev->tg or we can

	 * race with cgroup code which can read autogroup = prev under rq->lock.

	 * In the latter case for_each_thread() can not miss a migrating thread,

	 * cpu_cgroup_attach() must not be possible after cgroup_exit() and it

	 * can't be removed from thread list, we hold ->siglock.

	 * cpu_cgroup_attach() must not be possible after cgroup_task_exit()

	 * and it can't be removed from thread list, we hold ->siglock.

	 *

	 * If an exiting thread was already removed from thread list we rely on

	 * sched_autogroup_exit_task().